Steve McNamara, a spokesman for the Licensed Taxi Drivers Association said Miss Abbott was indulging in "the stereotypes of the 1960s" and said many of the LTDA's 9,000 drivers are black or Muslim.

"At worst she is racist and at best she is stupid in making comments like that. Either way, she should go," said Mr McNamara.

The 'Blackbusters' gaffe brings one of the most difficult weeks of Ed Miliband's tenure as Leader of the Opposition to a fittingly farcical conclusion.

It began with a broadside from Labour guru Lord Glasman, who wrote in the New Statesman that Ed Miliband had "no strategy and no narrative".

Then a memo written by party press chief Tom Baldwin that described Miliband as leading the "best recovery of any opposition party in the history of opposition parties" was leaked to a newspaper.

Last night Jim Murphy, shadow defence secretary, appeared to distance himself from Labour's attacks on Government spending cuts, saying the Labour party's credibility depended on rejecting "shallow and temporary" populism.

The Liberal Democrat press office tweeted: "We can confirm that we have not hacked Ed Miliband's Twitter account. That's all him."

Tom Jamieson, a writer for satirical magazine Private Eye, chipped in with a reworking of Mr Holness' catch-phrase, writing: "Ed Miliband would like an O please, Bob."